Hainan Airlines will fly between the capital and the Chinese capital of Beijing, it is to be announced tomorrow.
The flights will continue to and from Dublin.
An industry source said: "It is a route which the airport has been seeking for a long time."
Edinburgh has pursued direct Chinese flights for years because of their huge potential for bringing tourists to Scotland and developing business links.
Scottish ministers have described it as a "key priority" for route development.
Alex Salmond revealed in 2015 he had tried to persuade Hainan to launch flights to Prestwick the previous year - the airport the Scottish Government bought to save from closure in 2013.
Edinburgh Airport and Beijing Capital International Airport signed a ground-breaking partnership agreement last May.
They agreed to "collaborate to develop a shared understanding of markets and shared operational and commercial opportunities".
A new deal has also been struck between London and Beijing to increase the number of permitted flights between the UK and China, as Scotland on Sunday revealed in December.
It involved an extra 50 flights a week to and from non-London airports being allowed after the total from the UK was increased from 40 to 100 in 2016.
The UK Department for Transport said at the time: “Scotland’s airports could be set for the country’s first-ever scheduled services to China following a landmark deal on aviation access.”
A total of 41,000 visits were made from China to Scotland in 2016, which generated spending of Â£36 million.
Scottish exports to China reached Â£2.5 billion in the year to last September.
However, an industry observer feared Edinburgh could lose out to Dublin if the Irish capital generated more passengers and the Scottish leg was ditched by Hainan.
Ireland does not charge air passenger duty - which will add Â£83 per passenger to the cost of a ticket from Edinburgh - and the Scottish Government's plans to halve the tax have been shelved.
The observer said: "I’d be willing to bet the airline will eventually go direct from whichever airport has the strongest bookings and drop the other one completely.
"Mind you, for the Chinese tourism market, it might be a winner to offer both Scotland and Ireland on one trip.
"This is a good way to test the market."
He added that some Scots might even fly to Dublin to get cheaper fares.
He said: "I bet an advance-purchase business class ticket is lower from Ireland, possibly low enough to make it cheaper to book from Dublin and fly there on Ryanair."
The first non-London flights to China were launched from Birmingham in 2014.
Gordon Dewar, chief executive of Edinburgh Airport said at the time of the December announcement: “This is fantastic news and in my opinion brings the prospect of a direct Edinburgh China service even closer.”
A Scottish Government spokesman said at the time: “Securing direct links between Scotland and China is one of our key priorities for route development.
"We continue to work closely with airports and Chinese airlines to present a compelling case.
"The agreement with China is certainly helpful and we were pleased to be part of these negotiations.”
An Edinburgh Airport spokesman said today: "We would not comment on any speculation."